We published this paper in the Journal of Sports Science and Medicine. Unfortunately for the average runner and non-scientist it is full physiological and biomechanical terminology which can make it difficult to interpret. The purpose of this blog is to translate what we found into running speak.
How did we do it?
We had two speeds for runners to run at on a treadmill (see picture above) and we had two test conditions for runners to complete; one with no shoes and the other with a pair of neutral new balance shoes. We had two speeds so we could see what happens when runners are running at easy run pace (the most familiar pace to a runner) and at a faster pace a bit like a tempo run; in both cases with and without shoes (the order was randomly chosen for each runner). These were good runners, their average 1500m PB was 3:59 so certainly no slouches (they would probably win your local park run).
What did we find?
At lower speeds, we found that the majority of runners (at least 7 out of 9) tended to have a shorter stride length without shoes. This change in stride length also meant that there was a tendency towards the leg being less extended (straight) and having a bit more bend (flexion) particularly at the knee. At higher speeds changes were a lot more variable and lacked the more consistent pattern seen at the lower speed, which in science leads us to conclude that there were no real changes overall at the higher speed (even though some of the individual responses were most interesting).
What might this mean?
Firstly, it tells us that any changes that occur in stride patterns as a result of barefoot running seem to happen mainly at lower speeds. This is interesting to us as we know that runners spend ~75% of their training time at lower speeds. The shorter stride length is thought to be an advantage for injury prevention due to bringing the leg closer underneath your body weight so it can more easily support it compared to if it was out in front you (extended). The change in angles may mean that there are changes in muscle work. The only way to change a joint angle in normal circumstances is to use a muscle e.g. to bend your elbow you use your bicep. This might be important as it might help runners to use their muscles to control their landing instead of slapping or plodding along as I referred to in last week’s blog. This has potential to help with certain types of injuries and less so with other types of injuries. As I said last week if you wish to try this out I suggest you do small amounts (<15 minutes) on a soft grass surface to begin with, as we suggest in this paper.
Until next week – happy running! Peter